The utility model relates to an automatic change production water line that moulds plastics, including system of processing, conveyor system and cooling system, system of processing includes the pan feeding device, inhales material device, forming mechanism and fixture, and fixture includes firstly and the second manipulator, and first and second manipulators set up respectively above forming mechanism the slidable, and conveyor system includes main feed track and outwards extended a plurality of feed tracks of formation respectively by this main feed track, and the pan feeding device is located the both sides of main feed track respectively, and cooling system is connected with system of processing through the breathing pipe, the beneficial effect of the utility model embody: with the centralized transport of traditional production line through carrying the channel to carry out the product, make the product after each production line middle finishing is accomplished deposit a little through unified the assembling of main feed track, effectively accelerated production cycle, reduce the subsequent processing work in traditional course of working, reduce the processing cost, the plant use of being convenient for, the practicality is strong, and furtherly has optimized the degree of automation of production line.